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Business Combinations - Acquisition Method for Recording Business Combinations (Parenthetical) (Detail) | 3 Months Ended
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Mar. 31, 2019
Inverson Holding Company - Company, LLC (IHC) [Member] |
Business Acquisition [Line Items] |
Effective Date of Acquisition | Jan. 01, 2019
James Brown Inc. (JBI) [Member] |
Business Acquisition [Line Items] |
Effective Date of Acquisition | Jan. 01, 2019
Nine Other Acquisition [Member] |
Business Acquisition [Line Items] |
Effective Year of Acquisition | 2019

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